Enable more browser_tests on Dr. Memory bots now that we have more cycles due to using Release build.

BUG=http://code.google.com/p/drmemory/issues/detail?id=1429
TBR=zhaoqin@chromium.org

Review URL: https://codereview.chromium.org/154043004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248773 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248773